Composite lining for rotary furnaces



W. S. ROCKWELL. COMPOSITE LINING` FOR ROTARY FUHNACES.

APPLICATION FILED SEPT. B, |919.

Patented Mar. 9,1920.

w. s, RocKwELL. COMPOSITE LINING FOR ROTARY FURNACES.

APPLICATION FIL-ED SEPT'.8, |919.

Patented Mar. 9., 1920.

2 SHEETSJ-SHEET 2.

UNTTED STATES PATENT orrron.

"WALTER S. ROCKWELL, OF NEW YORK, N. Y., ASSIGNOR T0 W. S. ROCIIWELL' COMPANY,

' I 0F NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

COMPOSITE LINING FOR'ROTABY FURNACES.

Specification of Letters Patent.

Patented Mar. 9, 1920.

.Application ledr September 8,1919. Serial No. 322,571.

To all lwhom t may concern Beit known that I, lWALTER S. RooKwELL, a citizen of the United States, residing at 300 West 106 street, New York, county of New York, and State of New York, have invented certain new and useful Improvements in Composite Linings for Rotary Furnaces, fully described. and represented in the following specification and the accompanying drawings, forming a ,part of the same.

This invention relates to rotary furnaces of that class having a cylindrical shell with a lining of heat-insulating material, and a rib disposed spirally upon the interior of the lining to form a conveying channel, which propels the material to be heated from one end to the otherof the furnacechamber as the shell revolves.

In some furnacesof this class means are provided for automatically conveying the abrade the surface of the tile perceptibly,A

which is especially undesirable in cases where avery high temperature is required.

The object of the present invention is to substitute metal for the 'tile heretofore used in the rib, and to also furnish,`when required, a metallic protective covering for the inner surface of the brick or other refractory lining; thus forming the walls of the channel wholly of metal and preventing any contact of the material with the brick-work. Where the protective covering is employed, any kind of heat-insulating material, as asbestos, magnesia, &c., may be used to line the casi-ng instead of highly refractory brick.

The characteristic feature of the invention is the formation of the ribin sections which can be applied successively to the lining in the process of manufacture so as to produce a continuous spiral channel upon the interior of the lining.

` This invention may be embodied in a variety of forms some of which are illustrated in the annexed drawings; and the claims appended hereto are intended `to cover all such forms and their equivalents.

In the simplest form of the invention, the

spiral rib is formed of cast-metal and made integral with sections of a shield or covering' for-"the lining, or furnished with a flange to fit between the courses of the lining.

When the spaces between the ribs arel wide, as with a spiral of considerable pitch, the brick lining may be reinforced by metallic flanges inserted between the brick courses, but not projected beyond the inner surface of the same.

The bottom of the channel in which the `stock rolls is in such casey formed in part of the edges of these flanges, which sup ort the articles as they'roll, and prevent t eir wearing materially upon the lining.

The ribs may, if referred, be made in segmental sections like the bricks, and the ribbed lining formed by inserting the sections of rib and brick in alternate courses.

- Where a complete metallic covering for the lining is desired vsuch covering may be made vof curved segmental sections adapted to lie upon the surface of the brick between the ribs, the bricks and riib holding one another in place like the wedged blocks of an arch.

Heated air vto supply a fluid fuel burner for heating the furnace .may be readily obtai-ned from an air-heating chamber in a hood within which the outlet of a furnace moves as the furnace shell rotates.

The invention will be understood by reference to the annexed drawing, in which Figure l is a longitudinal section of a rotary furnace provided with one form of theinvention; Fig. 1a shows an alternative construction; Fig. 2 is an end elevation of the left-hand end of the furnacewith the burner-casing removed; Fig. 3 is a section of the furnace on the dotted line 3-3 in Fig. `1; Fig. 4 is an elevation of one of the metallic rib-sections; Fig. 5 is an edge-view of the same; and Fig. 6 a view of the inner end of the same. Fig. 7 is a cross section of the furnace on line 7--7 in Fig. v1; Fig. 8 is a longitudinal section of part of a furnace-shell, showing metallic reinforcing flanges in the brick-work between the ribs;

Y Fig.V 9 is an end-view, and Fig. 10 a sideview of one of the brick-tiles for the lining.

Fig. 11 is an end-view, -and Fig. 12 a sideview of one of the metallic cover-sections for the brick-linin The furnace is slown with va cylindrical shell 1 having flanges 2 at its opposite ends with flanged head-pieces 4 and 8.

The head-piece 4 has an opening 5 for the passage of the fuel and air from the burner, and the head-piece 8 is provided with a drum and hopper having throats or passages which communicate with the drum by suitable openings.

The body of the furnace is shown supported upon rolls 6 mounted upon a frame 6 and is rotated by suitable means.

All of the parts so far described are common in previous constructions.

The shell is shown lined with bricks 7 made in sections as shown in Figs. 9 and 10, of suitable shape to fit between flangesv 11 formed integral with the spiral rib ,12.

The flange 11 of the rib, as shown in Fig.

1, is made thinner than the rib, to form a shoulder 11 which is provided to retain the `Sections ofv a metallic shield or armor 13,

laid upon the surface of thebricks between the coils of the rib 12. One of these shieldsections 13 is shown in Figs. 11 and 12.

As the bricks lie in a spiral course, tapering sections 135 of the shield are needed at opposite ends of the shell, where the lining terminates with aplane surface to lit the end-flanges, as shown at the left-hand end -of Fig. 1.

Fig. 3 'shows notches 15 cut in the outer endsl of the flanges 11 to lighten the weight of such flanges and to improve the heat-insulatingl effect.

Figs. 4 and 5 show the flanges 11 without such notch, andy any similar construction may be employed with the same effect in holding a metallic rib between the courses of the brick lining.

The rib-sections in Figs. 4 and 5 are shown with a notch m and tongue m formed respectively upon opposite edges of the sections to interlock their edges when laid between. the bricks of the lining. Such lock may be provided whenever necessary.

v Fig. 8 shows a portion of a furnace-cylinderwith a spiral rib 12 of very considerable pitch, so that a broad surface ofthe brick lining is exposed between the rib-coils.

To increase the durability of such brick lining where the material rolls between the ribs, flanges 14 are shown inserted between the courses of the brick lining to form a reinforcement of its surface, the inner edges of the flanges being flush with the inner surface of the brick ining, and operating to support the material rolling upon the lining and to protect `the lining in great part from abrasion bythe material. l

Figi 1a' shows the shield-sections 13 Imade integral with the rib-sections 12', the length of the shield-sections beingv equal to the pitch L of thev rib so that the shields wholly cover the interior of the lining.` The ,alternate sections of the combined rib and shield are hatched in Fig. 1a showing the integral connection'of such parts, the intervening sections not being hatched, as the view represents the ends of such sections.

It will be seen from the above description that the different constructions all provide a metallic rib toform the spiral channel within the furnace-chamber. thus greatly increasing the durability of the spiral channel, and that the shield'or armor. surfaceprotection for the fire-brick lining may be made'integralvwith the rib, as shown in Fig. 1P, or in separate sections, as shown in Figs. 2, 11 and 12, and held inplace by engagement with the rib.

To avoid the necessity of any door lto close theV lateral discharge outlet 17, a hood 16 is formed to embrace the shell 1 at the outlet, except at the bottom, and is sustained close to the shell without' touching the same, so

as to largely prevent escape of gases from,

the outlet.

The sides or terminals 16 of the hood are extended downward below the casing, to guide the material discharged from vthe outlet, and a receptacle 22 is provided below the hood to receive the material.

Anarrow a, in Fig. 2 indicates the direction of rotation of the shell 1, and an arrow b the direction of movement of the material c (represented as round balls c) in the spiral channel and outlet.

The hood is enabled t o erform another .function by providing the ood with a surrounding air-jacket 18, which is shown extended around the upper portion of the hood where it lies close to the shell, and is highly heated by the hot gases and the radiant heat through the outlet 17 during the greater` part of the cycle. Air is circulated through the jacket by an inlet-pipe 19 and outletpipe 21, the latter of which is connected to the burner 23, shown at the left-hand end A of Fig. 1.

J The provision of the air-jacket enables the hood to perform the double function of ,closing the outlet 17 without using any door or mechanism to close the door: and also the preheating'of the air required for the combustion of the fuel in the furnace.

The radiant heat necessarily passes through the outlet 17 as the outlet moves around within the hood, and the provision of the preheating jacket upon the. hood efectually utilizes such radiant heat which would otherwise be lost.

An inlet-pipe 19 is connected to one end of the jacket and supplied with air under pressure, and a pipe 23 connects the opposite end of the jacket to a burner 21 shown at the left-hand end of Fig. 1. The air is highly heated by conduction from the radiant heat, and is thus fitted to promote combustion most effectively.

The hood prevents any material escape of the highly heated gases from the furnace as the outlet is carried around the inside of theI hood until the outlet reaches the lower side, when the adjacent material in the spiral channel falls through the outlet into any suitable receptacle 22, or into a bath of water or oil or other liquid if the stock requires to be chilled. 1.

r The use of the hood obviates the necessity of fitting a door to the outlet-opening f gases which escape within the hood, to heat the air in the surrounding jacket.

It will be noticed that in Fig. 1 a part of the ribs 11 and their flanges 12 are not hatched, as the section plane does not intersect those parts where the division between the parts lies in such plane. As the rib is formed of many such sections as appear in Fig. 4, and the sections are not aliquot parts of a circle, the divisions between the sections sometimes lie in the section-plane, and no f hatching is necessary.

In will be fully understood, by reference to Figs. 4. 5, and 9 to 12 inclusive how the parts of the structure are formed of seg ments, which may be applied successively to the interior of the shell from one end to the other, and serve to support and brace one another throughout the entire structure.

Having thus set forth the nature of the invention what is claiimed herein is:

1. In a rotary furnace. the combination, with a cylindrical shell, of a fire-brick lining neXt the shell and a metallic rib formed in sections projected inwardly from the lining and disposed spirallv upon the length of the furnace to form a feeding channel therein.

2. In a rotary furnace` the combination, with a cylindrical shell. of a fire-bri ck lining next the shell. a metallic rib projected inwardly from the lining and disposed 'spirally upon the length of the furnace. and a metallic reinforcement at the surface of the' a metallic rib projected inwardly from the -shoulders to engage the opposite edges of the guard covering to hold the same in place. Y

`5. In a rotary furnace, the combination, with a cylindrical shell, of a fire-brick lining ynext the shell, and ametallic rib projecte inwardly from the lining and disposedspi` rally within the same, the said lining and rib being made in segmental sections and mutually supporting one another within-the said shell.

6. A rotary furnace as described in claim 3 with the lining and rib made in segmental sections adapted to be inserted successively in the shell^from one end to the other.

7. In a rotary furnace, the combination,

segmental section being reduced in thickness where it extends between the coils of the lining, as and for the purpose set forth.

8. A rotary furnace as described in claim 6 with a tongue and notch upon the opposite edges of the section to engage one another when set within the shell.

9. In a rotary furnace, the combination,

with a f cylindrical shell having a lire-brick lining, and a spiral rib Within the lining to convey and a lateral outlet-opening at one end to discharge the material, of a stationary hood encircling the cylindrical shell around the path of thel said opening excepting at the bottom of the hood, the said hood avoiding the necessity of a door to prevent the escape of gases. y

10. In a rotary furnace, the combination, with a cylindrical shell having a refractory lining and a spiral rib within the lining to convey the material through the furnace, and a lateral outlet at one end to discharge the material, of a hood disposed about the shell in the path of the outlet to prevent escape of gases therefrom, and an air-jacket combined with said hood and heated by the radiant heat from the outlet, and means to 4circulate air through the said jacket and mingle the air with the fuel employed to heat the furnace.

the material through the furnace,

11. In a rotary furnace, the combination,

with a cylindrical shell having a refractory chamber, and means for circulating air lining, a spiral rib Within the lining to con-l through the said jacket and delivering it to 10 vey the material through the furnace, and the said burner, as and for the purpose set a lateral outlet at one end to discharge the forth.

material, of a stationary hood encircling the In testimony whereof I have hereunto set cylindrical shell around the path of the my hand.

said opening exceptin at the bottom of the v hood, a burner for eating the furnace- WALTER S. ROCKWELL. 

